The present application relates to a reflection plate used as, for example, a reflector of a self-luminous device such as an organic EL (Electroluminescence) device, a method of manufacturing the reflection plate and a light-emitting device using the reflection plate.
A self-luminous device such as an organic EL device includes a first electrode, an organic layer including a light-emitting layer and a second electrode in order on a substrate, and when a DC voltage is applied between the first electrode and the second electrode, electron-hole recombination occurs in the light-emitting layer to emit light. The emitted light may be extracted from, for example, the second electrode side, that is, from a side opposite to a side where a circuit including a TFT (Thin Film Transistor) or wiring is arranged so as to increase an aperture ratio. In the case where light is extracted from the second electrode side, a high reflective metal electrode is typically used as the first electrode.
In a light-emitting device in which a plurality of such organic EL devices are formed, a refractive index in the inside of the light-emitting device is high (for example, a refractive index of 1.5 or over), so total reflection easily occurs at an interface with an air layer (with a refractive index of 1.0). Therefore, it is difficult to sufficiently extract emitted light to outside. Therefore, a technique of arranging a reflection plate (reflector) on a light extraction side of an organic EL device has been proposed as described in Japanese Patent No. 3573393 and Published Japanese Translation No. 2005-531102 of PCT international application. In such a reflector, a plurality of projections are formed on a surface of a base so as to correspond to organic EL devices arranged, and a side surface of each projection is covered with a reflecting mirror film.